1. Field of the Invention
The present invention relates to a separation column for separating components in a liquid sample and a liquid chromatograph apparatus using thereof.
2. Description of the Related Art
In a high speed liquid chromatograph apparatus, a particle-filling column has been used as a column for separating components in a liquid sample. In recent years, however, a monolithic-type column is increasingly used, instead of the particle-filling column. A monolithic-type silica column, for example, is known as a monolithic-type column.
A monolithic-type silica column includes a narrow tube and a porous body inserted therein. The porous body is called a monolithic rod, a monolithic silica rod or the like. The porous body is a thin rod body. Therefore, it is very difficult to form a porous body with high precision such that the outside diameter of a cross section thereof is constant along the length direction. Thus, a gap is generally generated between a narrow tube and a porous body.
When passing through a porous body, a liquid leaks into the gap through an outer circumferential surface thereof. The liquid leaked into the gap flows inside the gap without going back into the porous body.
Japanese Patent Application Laid-Open No. 11-64314 proposes to provide a resin cladding material on the outer circumferential surface of a porous body to prevent leakage of a liquid from the outer circumferential surface of the porous body into a surrounding gap.
A resin cladding material to be attached to the outer circumferential surface of a porous body needs to have strong adhesive properties to porous bodies and also high-pressure resistance. It is difficult to find a material satisfying such conditions.
When passing through a porous body, a liquid comes into contact with a resin cladding material on the outer circumferential surface thereof. Thus, a volatile solvent in the resin cladding material is eluted, degrading separation performance.
An object of the present invention is to provide both a column having high-pressure resistance and capable of performing high-speed separation and analysis even with a small flow rate and a liquid chromatograph apparatus using the column.